Millimeter wave imaging devices are provided. A millimeter wave imaging device includes a housing and one or more heating elements inside the housing. The millimeter wave imaging device includes a flexible gasket on the housing. The millimeter wave imaging device includes a main lens attached to the housing by the flexible gasket. The millimeter wave imaging device includes a protective lens on an outer surface of the main lens. Moreover, the millimeter wave imaging device includes an Electromagnetic Impulse (EMI) filter attached to the housing and extending along an inner surface of the main lens. Methods of operating millimeter wave imaging devices are also provided.

A method serves for imaging polarimetry. A chipless, passive transponder which has a plurality of surface regions with different polarimetric properties is illuminated fully polarimetrically by radar radiation. At least one polarization-encoded image of the transponder is generated using the radar radiation reflected thereby, and the different surface regions of the transponder in the polarization-encoded image can be recognized by their at least one polarimetric property. The passive, chipless transponder has at least two surface regions with different polarimetric structures.

A system including a plurality of circuits in a first radio frequency (RF) device which are configured to control a plurality of reflector devices based on a set of criteria. The controlled plurality of reflector devices transmit a plurality of RF signals in a specified direction and a specified location of a second RF device within transmission range of the controlled plurality of reflector devices. The plurality of RF signals are transmitted in the specified direction and the specified location of a second RF device based on a request for signal cancellation. The request for the signal cancellation is based on a noise from the second RF device and the plurality of RF signals are cancelled in the specified direction and the specified location of the second RF device.

For example, a system may include a radome to be attached to a vehicle bumper fascia; an antenna array on a Printed Circuit Board (PCB), the antenna array is between the PCB and the radome, the antenna array comprising a Transmit (Tx) antenna configured to transmit Tx radar signals via the radome and the vehicle bumper fascia, and a receive (Rx) antenna configured to receive Rx radar signals based on the Tx radar signals; and an absorbing spacer in a spacer area between the PCB and the radome, the spacer area separating the Tx antenna from the Rx antenna, the absorbing spacer configured to absorb reflected signals formed by reflection of the Tx radar signals from the vehicle bumper fascia.